THIS invention relates to a method of and system for monitoring shaft signals associated with a shaft of a rotating machine.
Rotating machines having shafts such as large generators often have various physical phenomena associated therewith, for example, magnetic forces in the generator, static rubbing of steam on the turbine blades, or the like. These physical phenomena often result in voltages arising on the generator shaft and also currents flowing along it. It will be understood that this voltage and current information contains data associated with the condition of the generator, for example data associated with a rotor, stator and frame of the generator. Conventionally, these voltages and currents are obtained from voltage and current brushes mounted near the generator shaft, and arranged to contact the generator shaft.
Methods which evaluate the condition of rotating machines often can only be applied off-line and the on-line methods require expensive, permanently mounted hardware and expensive interpretation hardware which can only look at a single piece of information.
In this regard it is an object of the invention at least to analyse the signals on a shaft of a rotating machine, such as a generator, more efficiently and in a more cost effective manner thereby to determine a condition of the rotating machine.